Quuxplusone added inline comments.
================ Comment at: clang/include/clang/Basic/AttrDocs.td:4087-4088 -Marking virtual functions as ``not_tail_called`` is an error: +Marking virtual functions as ``not_tail_called`` will not have effect on the +overriding functions of derived classes: ---------------- ahatanak wrote: > Quuxplusone wrote: > > aaron.ballman wrote: > > > > > /will not have effect/will have no effect/ > > However, this phrasing is easy to interpret the wrong way around: actually > > marking a (base-class) virtual function //will// affect overriding > > functions in derived classes! You meant that marking the //overrider// > > wouldn't retroactively affect the //overridden// function from the base > > class. > > I think the correct explanation would be more like this: > > > > Generally, marking an overriding virtual function as > > ``not_tail_called`` is > > not useful, because this attribute is a property of the static type. > > Calls > > made through a pointer or reference to the base class type will respect > > the ``no_tail_called`` attribute of the base class's member function, > > regardless of the runtime destination of the call. > > > > I think it'd also be correct and helpful to add: > > > > Similarly, calls made through a function pointer will respect the > > ``no_tail_called`` attribute of the function pointer, not of its > > runtime destination. > > > > (I admit this is mildly redundant with the `foo2` example above.) > > calls made through a function pointer will respect the ``no_tail_called`` > > attribute of the function pointer > > But function pointers currently can't be annotated with `no_tail_called`, > right? Ah, maybe. By "will respect the not-tail-called attribute of the function pointer," I meant both "will not-tail-call it if it has the attribute" and also "may tail-call it if it lacks the attribute." Sounds like only the latter is hittable today (as shown in the `foo2` example). Also, I notice that everyone (including me) keeps misspelling the name of this attribute. I wish it were spelled as a command, like "nodiscard" — e.g. "notailcall" or "do_not_tail_call" — but I assume that ship has sailed? Anyway, apparently `not_tail_called` is the current spelling, and we should make sure the docs use it consistently :) Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D96832/new/ https://reviews.llvm.org/D96832 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
